If you go to the 'User Device Logs' from Outsystems Now Service module (<yourserver>/OutSystemsNowService/UserDevice_List.aspx), you can see the list of all devices that accessed your environment via Outsystems Now. To check the push token you must hover with your mousethe 'Push Token' icon (Check the image below).

Do you see any device on your list? If not you need to install the Outsystems Now on your device, and access to your environment with it. After that you should see the device on that list and the push token. The GCM API key (Server or Browser key) it's only needed during the configuration of your application on pushwoosh control panel (https://cp.pushwoosh.com).

For the moment we are trying a different route. We have a skinned shell and there seems to be a problem with it. We are reverting to the standard OutSystems shell. We are receiving the token now. In the site properties we are asked for Site.PushWoosh_ApplicationIdandSite.PushWoosh_Auth. When I log into my PushWoosh Account I cant find this Auth.